Abstract: A simple and robust nonlinear dilatation constitutive model with clear mechanics concept is introduced, and the stiffness coefficient matrix of constitutive relationship is presented. A kind of coarsed-grained soil is collected from a rockfill dam, and true triaxial consolidated drained shear tests with different values of b are conducted. The comparison between the calculated and test results is employed to validate the nonlinear dilatation model. On this basis, the nonlinear dilatation model and Ducan-Chang E-B model are taken into account respectively to simulate the whole process of layered filling of dam, staged construction of face slab and staged impoundment. Based on the calculated results, the stress-strain relationships of dam body and concrete face slab are compared. Finally, the nonlinear dilatation constitutive model is verified to be available in the static finite element analysis of concrete face rockfill dams.